Exponential trichotomy and global linearization of non-autonomous differential equations

Abstract

Hartman-Grobman theorem was initially extended to the non-autonomous cases by Palmer. Usually, dichotomy is an essential condition of Palmer's linearization theorem. Is Palmer's linearization theorem valid for the systems with trichotomy? In this paper, we obtain new versions of the linearization theorem if linear system admits exponential trichotomy on $\mathbb{R}$. { Furthermore, the equivalent function $\mathcal{H}(t,x)$ and its inverse $\mathcal{L}(t,y)$ of our linearization theorems are Hölder continuous}. In addition, if a system is periodic, we find the equivalent function $\mathcal{H}(t,x)$ and its inverse $\mathcal{L}(t,y)$ of our linearization theorems do not have periodicity or asymptotical periodicity. To the best of our knowledge, this is the first paper studying the linearization with exponential trichotomy.